# Pharmacist follow-up of patients prescribed nirmatrelvir/ritonavir: a single-center retrospective analysis

## TL;DR

A study found that many patients did not follow instructions when prescribed NMV/r, highlighting the need for pharmacist follow-ups to ensure safe medication use.

## Contribution

The study provides real-world insights into adherence and medication management issues with NMV/r in clinical practice.

## Key findings

- 9% of patients took NMV/r contrary to physician instructions, including dosage misuse and self-interruption.
- 50% of patients did not follow instructions to discontinue regular medications.
- Post-prescription issues included forgetting to resume medications or stopping them at their own discretion.

## Abstract

Nirmatrelvir/ritonavir (NMV/r), a drug used to treat coronavirus disease 2019, has raised concerns about potential drug-drug interactions with concomitant medications due to cytochrome P450 3 A inhibition. However, limited data exist on its use alongside concomitant medications in clinical practice.

In this study, we conducted a retrospective survey using electronic medical records of 32 outpatients whose physicians instructed them to temporarily withdraw some of their regular medications. Medication status and adherence with instructions for the temporary withdrawal of concomitant medications were assessed via telephone. The results showed that three of the 32 patients (9%) took NMV/r contrary to their physician’s instructions, two of whom misused the dosage and one who self-interrupted the treatment. Additionally, 16 patients (50%) did not follow instructions to discontinue their regular medication. Beyond NMV/r adherence, potential post-prescription issues were identified, such as forgetting to resume regular medications or discontinuing medications at the patient’s discretion.

Post-prescription pharmacist follow-ups may improve adherence to NMV/r and support the safe management of regular medications. Future studies are needed to optimize NMV/r use in clinical practice.